Flaky test - 'reject dial of connection above closeAbove'

[achingbrain]

CI sometimes breaks on this test https://github.com/libp2p/js-libp2p-tcp/actions/runs/3971032097/jobs/6814690159

  1) close server on maxConnections
       reject dial of connection above closeAbove:
     Socket[1] connect ECONNREFUSED ::1:9900
  Error: connect ECONNREFUSED ::1:9900
      at TCPConnectWrap.afterConnect [as oncomplete] (node:net:1487:16)

The test is supposed to allow the first 3 connections (socket[1], socket[2], socket[3]). However, the first attempted socket fails to connect as apparently the server is not listening. The server should listen here and this promise resolve only when sockets can connect.

js-libp2p-tcp/test/max-connections-close.spec.ts

Line 28 in 07a03ac

await listener.listen(multiaddr(`/ip4/127.0.0.1/tcp/${port}`))

From what I can see in the test, the error message comes from this line. The socket is created here and attempts to connect to the port listened on here, so the .listen function may be returning before the socket is fully open? Maybe something OS-specific?